Wrench



(No Model.)

M. E. GAMPFIELD.

WRENCH.

Patented Oct. 11,1887

17 jjgi Hlllllllllllll p UNITED STATES PATENT OFFICE.

MATTHEW E. OAMPFIELD, OF ALLEGHENY, ASSIGNOR TO A. F. ALLEN BROWN, OFwPITTSBURG, PENNSYLVANIA.

.WRENCH.

SPECIFICATION fOrming part of Letters Patent No. 371,302, dated October11, 1887.

Application filed May 28, 1887. Serial No. 239,684. (No model.)

To all whom, it may concern.-

l for the finger-piece of the dog D.

It is also Be it known that I, MATTHEW E. CAMP- 1 formed with a chamber,in rear of its grip- FIELD, a citizen of the United States, residingping-face for the reception of the body of the at Allegheny, in thecounty of Allegheny and State of Pennsylvania, have invented certain newand useful Improvements in Wrenches; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

Myinvention relates to the class of wrenches known as monkey-wrenches,in which there is a fixed and a movable jaw; and it has especialreference to the kind of monkey wrenches in which the movable jaw has afree' sliding movement toward and from the fixed jaw, whereby it iscapable of being easily and quickly adjusted to differentsized nuts, andwhen so adjusted is locked in position. These wrenches are known asrapid transit wrenches, in contradistinetion to those in which the jawis moved and adjusted by screw or other mechanical action.

The invention consists, essentially, in the construction of the movablejaw, in the combination therewith of a springactuated, dog which isadapted to engage automatically with the serrated or toothed shank uponwhich the jaw slides to lock the latter against backward movement, andin the construction of the dog, whereby it is adapted to be convenientlydisengaged from the shank to allow the jaw to be moved backward.

In the accompanying drawings, which illustrate my invention, Figure 1represents a longitudinal section of a wrench embodying my invention.Fig. 2 is a front view of the same, and Fig. 3 a perspective view of thedog which holds the movable jaw.

A designates the shank of the wrench; B, the rigid jaw; G, the movablejaw, and D the dog, which holds the movable j aw against backwardmovement on the shank.

The shank A is serrated on the side on which the jaws are located, theserrations extending entirely across and forming teeth with which thedog engages to hold the movable jaw.

The jaw O is mounted on the shank A, to

slide back and forth, as usual in this class of wrenches, and is cut outat c to form a recess dog D, which chamber opens at the bottom into therecess a, through which the dog D is introduced. An overhanging lip, 0at the top of the recess, together with the vertical wall of thechamber, forms a seat for the front end of the dog, as represented inFig. 1.

The dog D is formed substantially as represented in Figs. 1 and 3, witha body portion, d, and a head, d, the lower face of the head (1 beingformed atan angle with the body d, so that when in position it will beparallel with the shank A. It is provided with teeth to match and engagewith the teeth of the shank A. In its head is a spring-seated pin, (V,which projects from the same and bears against the rear wall of thechamber 0, whereby it serves not only to press the jaw forward and holdit to its seat, butralso to press the head down into engagement with theshank A.

The head of the dog is provided with integral side flanges, d d whichoverhang the shank A and project out flush with the jaw, formingfinger-pieces by which the dog is pressed out of engagen'ient with theteeth of the shank to release the jaw and enable it to slide back on theshank A to open the wrench.

The rear inclined face of the sliding jaw C is concaved or hollowed out,and the chamber a is cut through the same. The body of the dog D issubstantially straight, and when the parts are in position projects outof its chamber, and its upper face or edge stands above the concavedsurface ofthejaw. This permits the dog to be pressed down and held inengagement with the shank in the event of the spring becominginoperative or the teeth becoming worn so as no longer to hold securely.

The dog is introduced into its chamber through the opening in the bottomof the latter before the jaw is placed upon the shank,

and it can only be removed in the same way.

Having thus described my invention, I claim as new 1. The sliding jaw O,concaved on its rear inclined face and chambered and recessed, as

described, in combination with the serrated or toothed shank A, and withthe dog D, seated in the chamber in said jaw and having a toothed orserrated head to engage the serrations of the shank, the upper side ofthe body of said dog lying above the concaved surface of the jaw,whereby the dog is adapted to be pressed into engagement with the shankby hand, substantially as shown and described.

2. The sliding jaw O, concaved on its rear inclined face and chamberedand recessed, as

described, in combination with the serrated or toothed shank A, and withthe dog D, seated in the chamber in said jaw, the said dog be ing formedwitha head, d, and integral side flanges, (1 d the latter extending intothe recess c and laterally beyond the shank on both I

